The present invention relates to compositions useful in electroluminescent devices and to such devices. More particularly the present invention relates to a device of the light emitting diode type exhibiting a spectral output which can be adjusted to wavelength in the regoin of 1.06.mu.m suitable for matching to optical fibers for communication purposes.
Light emitting diodes which emit radiation in the infrared region have been made from the materials GaAs and InP. These have been made both by liquid phase epitaxial growth and vapor phase epitaxial growth. These devices suffer from the limitations in that their emission at fixed wavelengths of 0.90 - 0.98.mu.m are not suitable for fiber optics communication because of available optical fibers having a spectral transmission window of 1.06.mu.m wavelength.